1. Field of the Invention
The present invention relates to an imaging lens and an electronic apparatus including the same.
2. Description of the Related Art
In recent years, as use of portable electronic devices (e.g., mobile phones and digital cameras) becomes ubiquitous, much effort has been put into reducing dimensions of portable electronic devices. Moreover, as dimensions of charged coupled device (CCD) and complementary metal-oxide semiconductor (CMOS) based optical sensors are reduced, dimensions of imaging lenses for use with the optical sensors must be correspondingly reduced without significantly compromising optical performance.
However, the conventional imaging lens with four lens elements is insufficient to satisfy consumer expectations of high image quality. It is desirable to develop an imaging lens that has a relatively small size and relatively high image quality.
Each of U.S. Pat. Nos. 7,480,105, 7,639,432, 7,486,449 and 7,684,127 discloses a type of an imaging lens that includes five lens elements. In each of U.S. Pat. Nos. 7,480,105 and 7,639,432, the first two lens elements of the imaging lens disclosed therein respectively have a negative refractive power and a positive refractive power. In each of U.S. Pat. Nos. 7,486,449 and 7,684,127, both of the first two lens elements of the imaging lens disclosed therein have a negative refractive power. However, the aforesaid arrangement of the first two lens elements is unable to achieve good optical performance. Beside, the imaging lenses disclosed in the aforesaid patents have a system length ranging between 10 mm and 18 mm, which disfavors reducing thickness of portable electronic devices.
Reducing the system length of the imaging lens while maintaining satisfactory optical performance is always a goal in the industry.